Speaking of hope B....if H is saying he is remorseful (saying he should throw things at himself, etc), and is saying he is willing to work on the M, then that's the most anyone could ask for...a fighting chance. Nothing on earth ever happened without that first step.
I can only imagine the amount of stress you would feel attempting this R this way. Please don't beat yourself about detachment while this Retrothing plays out. Go easy on yourself!
In many ways this is going to be a point where you're going to have to take a controlled risk letting your heart be open to a degree, or how else can you try to reconnect? If it works out really well then be ever so careful with yourself, but keep taking the baby steps. If it doesn't work out then it's awful but you are kind of dealing with that already. If somewhere in the middle then he's still risking the most important aspect of his time here on earth, and you could be open to seeing what the world offers you.
Everyone here is with you heart and soul through this. You're loved and not alone at all.